// Copyright 2011 Google Inc.
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//   may be used to endorse or promote products derived from this software
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#include "engine/context.hpp"

#include "utils/env.hpp"
#include "utils/fs/operations.hpp"

namespace fs = utils::fs;


/// Internal implementation of a context.
struct engine::context::impl {
    /// The current working directory.
    fs::path _cwd;

    /// The environment variables.
    std::map< std::string, std::string > _env;

    /// Constructor.
    ///
    /// \param cwd_ The current working directory.
    /// \param env_ The environment variables.
    impl(const fs::path& cwd_,
         const std::map< std::string, std::string >& env_) :
        _cwd(cwd_),
        _env(env_)
    {
    }

    /// Equality comparator.
    ///
    /// \param other The object to compare to.
    ///
    /// \return True if the two objects are equal; false otherwise.
    bool
    operator==(const impl& other) const
    {
        return _cwd == other._cwd && _env == other._env;
    }
};


/// Constructs a new context.
///
/// \param cwd_ The current working directory.
/// \param env_ The environment variables.
engine::context::context(const fs::path& cwd_,
                         const std::map< std::string, std::string >& env_) :
    _pimpl(new impl(cwd_, env_))
{
}


/// Destructor.
engine::context::~context(void)
{
}


/// Constructs a new context based on the current environment.
engine::context
engine::context::current(void)
{
    return context(fs::current_path(), utils::getallenv());
}


/// Returns the current working directory of the context.
///
/// \return A path.
const fs::path&
engine::context::cwd(void) const
{
    return _pimpl->_cwd;
}


/// Returns the environment variables of the context.
///
/// \return A variable name to variable value mapping.
const std::map< std::string, std::string >&
engine::context::env(void) const
{
    return _pimpl->_env;
}


/// Equality comparator.
///
/// \param other The object to compare to.
///
/// \return True if the two objects are equal; false otherwise.
bool
engine::context::operator==(const context& other) const
{
    return *_pimpl == *other._pimpl;
}
